title: Prediction of coronary artery stenosis using strain imaging diastolic index at rest in patients with preserved ejection fraction.
abstract: BACKGROUND
  Post-ischemic myocardial diastolic stunning persists for a long time after transient ischemia even after systolic function has recovered. We sought to identify coronary artery stenosis in clinical patients using strain imaging diastolic index (SI-DI) at rest.
  
  
  METHODS
  We retrospectively examined 85 patients with suspected coronary artery disease and preserved ejection fraction (EF; >50%) who underwent both echocardiography and coronary angiography. Speckle tracking strains were measured in 3 apical views and parasternal left ventricular (LV) short-axis views at the papillary muscle level. LV segments with inadequate image quality and deficit segments in the movie were excluded by the blinded observer. After strain analysis, LV segments were classified into no stenosis (≤ 50%), mild stenosis (51-75%), and severe stenosis (>75%) groups on the bases of the coronary angiogram.
  
  
  RESULTS
  SI-DI decreased significantly in severe stenosis segments (p<0.05, ANOVA), but none of the peak strains showed significant difference. The area under the curve for predicting severe stenosis in radial, longitudinal, and transverse SI-DI was 0.72, 0.74, and 0.80, respectively. A cut-off value of 49 for transverse SI-DI can predict LV segments with severe stenosis with sensitivity of 0.79 and specificity of 0.73. A screening cut-off value of 63 for transverse SI-DI shows sensitivity of 0.95 and specificity of 0.50.
  
  
  CONCLUSIONS
  SI-DI at rest is a novel marker in predicting coronary stenosis even in patients with preserved EF. This index can be used to screen patients with suspected coronary artery disease in routine echocardiography and does not require stress provocation.
authors.affiliation: Department of Cardiovascular Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. kimurak-int@h.u-tokyo.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Kimura
authors.forename: Katsu
authors.initials: K
authors.lastname: Takenaka
authors.forename: XiaoFang
authors.initials: X
authors.lastname: Pan
authors.forename: Aya
authors.initials: A
authors.lastname: Ebihara
authors.forename: Kansei
authors.initials: K
authors.lastname: Uno
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Fukuda
authors.forename: Takahide
authors.initials: T
authors.lastname: Kohro
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Morita
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yatomi
authors.forename: Ryozo
authors.initials: R
authors.lastname: Nagai
mesh_terms: D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis*; D003971:Diastole; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D013599:Systole